Input validation Download

for loops, strings, java swing Student approved


Every web site on the internet that takes input from a user has to validate that it's good input. And all those professional engineers write code that's like the code you're going to write here!


Make a helper method called isAllAlpha(String str). This method should return true if every character in str is a letter, upper or lower case.

Starter code

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class ValidateForm
   public static void main(String[] args)
      EventQueue.invokeLater(new Runnable()
            public void run()
               TextComponentFrame frame = new TextComponentFrame();

 * A frame with sample text components.
class TextComponentFrame extends JFrame
   public TextComponentFrame()
      setTitle("Subscription Form");

      final JTextField personName = new JTextField();
      final JTextField emailField = new JTextField();
      final JTextField zipCode = new JTextField();
      final JTextField birthDate = new JTextField();
      final JTextField phone= new JTextField();
      final JPasswordField passwordField = new JPasswordField();
      JPanel northPanel = new JPanel();
      northPanel.setLayout(new GridLayout(6, 6)); //dimensons of layout
      northPanel.add(new JLabel("Name :  ", SwingConstants.RIGHT));
      northPanel.add(new JLabel("Password :  ", SwingConstants.RIGHT));
      northPanel.add(new JLabel("Email : ", SwingConstants.RIGHT));
      northPanel.add(new JLabel("Zip Code : ", SwingConstants.RIGHT));
      northPanel.add(new JLabel("Year of Birth: ", SwingConstants.RIGHT));
      northPanel.add(new JLabel("Phone Number: ", SwingConstants.RIGHT));

      add(northPanel, BorderLayout.NORTH);

      final JTextArea textArea = new JTextArea(8, 40);
      JScrollPane scrollPane = new JScrollPane(textArea);

      add(scrollPane, BorderLayout.CENTER);

      // add button to append text into the text area

      JPanel southPanel = new JPanel();

      JButton insertButton = new JButton("Insert");
      insertButton.addActionListener(new ActionListener()
            public void actionPerformed(ActionEvent event)
                char[] cPssword  = passwordField.getPassword();

   //    ****************************   CHANGE CODE ABOVE   AT OWN RISK           ******************************* 
    //*********************  Here is where the action is performed!!!!              
                String candidateName = personName.getText() ;
                String candidateEmail = emailField.getText();
                String candidateZipCode = zipCode.getText();
                String candidatebirthDate = birthDate.getText();
                String candidatePhone = phone.getText(); 
                String candidatePassWord = new String(cPssword);
                textArea.append("here is where you append text to display");
   //    ****************************       CHANGE CODE BELOW AT OWN RISK    ******************************* 

      add(southPanel, BorderLayout.SOUTH);

      // add a text area with scroll bars


   public static final int DEFAULT_WIDTH = 300;
   public static final int DEFAULT_HEIGHT = 300;

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